METHODS AND SYSTEMS FOR DELIVERY OF THERMAL ENERGY

A system and method of recovering hydrocarbons located at or above a sea floor of a sea are disclosed. The method includes heating a working fluid at a heater and delivering the working fluid downward into the sea through a first string of a riser to a heat exchanger. The riser has a plurality of strings in a concentric arrangement. The heat exchanger transfers thermal energy from the working fluid to at least hydrocarbons to enable recovery of the hydrocarbons through a second string of the riser. The working fluid returns from the heat exchanger to the heater through a third string of the riser.